The present disclosure relates to the field of mechanical ventilation for patients undergoing general anesthesia. More specifically, the present disclosure relates to a system and method for controlling the introduction of fresh gas into a breathing circuit.
Mechanical ventilation support is a common therapeutic technique that is provided to a patient that is either too weak from sedation or muscle paralysis to complete a respiratory cycle without external assistance. Artificial ventilation is provided to patient's experiencing total pulmonary failure and is unable to initiate a respiratory cycle under their own power. Ventilatory assistance is provided to patient's that can initiate spontaneous breathing, but benefit from the external control of the volume duration, and inhaled concentrations provided with ventilatory assistance.
Previous mechanical ventilation systems vented expired gases away from the patient and each breath included only fresh gas. Modern mechanical ventilation systems recycle at least a portion of the expired gases from the patient by processing the expired gases and returning them to the patient in a later respiratory cycle. These, low-flow mechanical ventilation systems seek to maximize the use of medical gases delivered to the patient.